Capter 3&4 small engines

Insert

A valve seat ____ is a separate machined engine component pressed into the cylinder block that provides the sealing surface for a valve

----

A(n) _____ is the removable section of a two-piece connecting rod that provides a bearing surface for the crankpin journal

ingestion

Abrasive____ is a cause of engine failure through the undesirable introduction of abrasive particles into a small engine

piston head

A(n) ____is the top surface of the piston, which is subjected to tremendous forces and heat during normal operation

racker arm

A(n)___ is an engine component that acts as a pivoting device for opening and closing overhead valves

interference

A(n)____ angle is the intentional deviation from a specification of two mating machine components to improve seating quality after a sufficient break in period

Overhead valve

A(n)____ engine is an engine that has valves and related components located in the cylinder head

glow plug

A(n)____ is a Diesel engine component that preheats air inside the combustion chamber to facilitate ignition of the charge

piston

A(n)____ is a cylindrical engine component that slides back and forth in the cylinder bore by forces produced during the combustion process

Cam lob

A(n)____ is an egg-shaped protrusion on the camshaft that moves a tappet to open a valve

Crankcase

A(n)____ is an engine component that houses and supports the crankshaft

connecting rod

A(n)____ is an engine component that transfers motion from the piston to the crankshaft and functions as a lever arm

race

A(n)____ is the bearing surface in an anti-friction bearing that supports rolling elements during rotation

Head gasket

A(n)____ is the filler material placed between the cylinder block and cylinder head to seal the combustion chamber

Bearing

A(n)____ journal is a precision ground surface within which the crankshaft rotates

turbine

A(n)___is a component that provides a turbocharger with the needed rotational force to compress ambient air to a positive pressure

reduced

As the piston moves toward TDC, The volume of the combustion chamber is ____

Piston

During compression, heat is produced from the work applied by the _____

Windows

Piston ____ are a series of small holes machined into the oil ring groove surface of the piston.

2

Small engines commonly have____ valves per cylinder

prony brake

The ____ dynamometer is a dynamometer used to measure engine torque using a brake that exerts pressure on a spring scale

throw

The ____ is the measurement from the center of the crankshaft to the center of the crankpin journal, which is used to determine the stroke of an engine

Charge

The ____ is the volume of compressed air-fuel mixture trapped inside the combustion chamber ready for ignition

ring

The piston_____ should be expanded only enough to slide over the head of the piston

face

The valve ____ is the machine surface of a valve that mates with the valve seat to seal the combustion chamber

valving system

The___ in a two-stroke cycle engine requires fewer parts, making it lighter in weight than a four-stroke cycle engine

power

The____ event is an engine operation event in which hot expanding gases force the piston head away from the cylinder head

crank gear

The____ is a gear located on the crankshaft that is used to drive other parts of an engine

Sump

The____ is a removable part of the engine crankcase that serves as an oil reservoir and provides access to internal parts

Engine block

The____ is the main structure of an engine which supports and helps maintain alignment of internal and external components

skirt

The____ of a piston is the portion of the piston closest to the crankshaft that helps align the piston as it moves in the cylinder bore

Stroke

The____ of an engine is the linear distance that a piston travels in the cylinder bore from top dead center to bottom dead center

overlap

Valve____ is the period during engine operation when both intake and exhaust valves are open at the same time

Vapor

When gasoline is heated, it changes rapidly from a liquid to a(n)_____

Break-in

____ is the process that causes the running surfaces of piston rings and the surface of the cylinder bore to conform to each other

side

____ loading is the application of an undesirable unilateral force to an engine. component or components

Thermal

_____ conductivity is the ability of a material to conduct and transfer heat

thermal

_____ efficiency is a measurement that compares the amount of chemical energy available in fuel converted into heat energy used to produce useful work

Thermal

_____ growth is the increase in size of a material when heated, with little or no change back to original dimensions

Hardfacing

_____ is the application of material to an engine component to improve wear resistance from load, heat, and chemical corrosion

innerent

_____ pressure is the internal spring force that expands a piston ring based on the diagnosis and properties of the material used

Austenitic

_____ steel is a heat-resistive metal alloy consisting of cobalt, tungsten, and chromium

conesion

______ is the molecular attraction by which atoms and molecules are united throughout the mass

transesterification

_____is a chemical process used to produce biodiesel fuel, where glycerin is separated from fat or vegetable oil

Preignition

_____is an undesirable engine condition which occurs when a small portion of a combustion chamber component or a particle in the combustion chamber becomes excessively heated and ignites the charge as it enters the combustion chamber

brake

____horsepower, or shaft horsepower, is the amount of usable power taken from an engine